Device for introducing a weft thread into a shed



6, 1968 H. P. VAN MULLEKOM 3,367,371

DEVICE FOR INTRODUCING A WEFT THREAD INTO A SHED Filed Feb. 16, 1966 3sheets'sheet 1 Feb. 6, 1968 H. P. VAN MULLEKOM 3,367,371

DEVICE FOR INTRODUCING A WEFT THREAD INTO A SHED 5 Sheets-Sheet 2 FiledFeb. 16, 1966 1968 H. P. VAN MULLEKO'M 3,367,371

DEVICE FOR INTRODUCING A WEFT THREAD INTO A SHED Filed Feb. 16, 1966Ksheetsfihcet 5 FIGQ United States Patent 3,367,371 DEVICE FORINTRODUCING A WEFT THREAD INTO A SHED Hubert Peter van Mullekom, Deurne,North-Brabant, Netherlands, assiguor to N.V. Machinefabriek L. toStrake, Deurne, North-Brabant, Netherlands, a Dutch company Filed Feb.16, 1966, Ser. No. 527,654 Claims priority, application Netherlands,Feb. 23, 1965,

5-2,271 6 Claims. (Cl. 139127) ABSTRACT OF THE DISGLOSURE A device forintroducing a weft thread into a shed, comprising a nozzle for blowing astream of air, a passage having an outlet end adjacent the stream of airissuing from the nozzle, and having an inlet end into which secondaryair is drawn by the jet action of the stream of air issuing from thenozzle in order to entrain an end of the weft thread presented at theinlet end of the passage, and to carry such end of the thread throughthe passage to a point at which such end of the thread is entrained bythe stream of air issuing from the nozzle to cause a length of the weftthread to be drawn through the passage and blown into the shed, a needlehaving a notch in its point, and mechanism for guiding the needle foraxial movement from one extreme position in which the needle isretracted out of the path of the weft thread entering the passage,through an intermediate position in which the notch in the point of theneedle engages a weft thread at the inlet end of the passage, to anotherextreme position in which the needle extends into the passage andpresents the weft thread inside of the passage.

Background 0 the invention The invention relates to a weft insertingdevice, provided with a jet nozzle for blowing a weft into a shed bymeans of air under pressure, which weft inserting device is providedwith a passage for the thread, which comes from a thread package.

Such weft inserting devices for looms are known per se.

When the production speed of such looms is increased the holding of thethread for its conveyance becomes more critical. It can happen that thethread will lag with respect to the other moving parts of the loom. Sucha lag is inadmissable.

Summary 0) the invention The object of the invention is to improve aweft inserting device in such a manner that the thread can be launchedvery quickly.

According to the invention this is attained in that a needle extendsinto a passage, which needle at its point is provided with a notch,which is adapted to receive a thread running in front of the point ofsaid needle, which needle is adapted to move axially between two endpositions, while in one end position the thread is positioned within thepassage with the point of the needle near a jet nozzle and in the otherend position at the end of the passage opposed to the jet nozzle theneedle is entirely free from the path of the thread to the passage.

The invention makes it possible to present the leading part of thethread on which air under pressure of the jet nozzle acts firstly in theshape of a loop to this air under pressure, so that the air has a goodgrip on this leading end.

Moreover the invention has the advantage that the thread can be morequickly supplied to the jet nozzle and 3,367,371 Patented Feb. 6, 1968begins to move before the secondary air, which is sucked to the passageby the jet action has a sufiicient speed to propel the thread throughthe passage.

The invention can be also applied to a loom in which a shaft for suckingin a loop of a measured part of the thread is connected to the weftinserting device as known per se.

According to the invention the loom is constructed in such a manner,that the shaft is provided with an entrance opening for the needle,which entrance opening and the needle are positioned in such a mannerwith respect to the interior of the shaft, that upon the movement of theneedle its point crosses the path of the thread in front of the mouth ofthe shaft. The leading end of the thread remaining in the shaft is thenimmediately presented to the blowing device through the passage by theaction of the needle.

A practical embodiment according to the invention is attained in thatthe passage for the thread is situated between a jet nozzle and themouth of the shaft, which passage is shaped in such a manner that itscross section decreases from the mouth of the shaft in the directiontowards said jet nozzle.

It is preferable that the entrance opening for the needle at least atthe mouth of the shaft be positioned in a plane of symmetry between thesmall sides of the cleft-like shaft opening and that the needle, whichis positioned in this plane of symmetry of the interior of the shaft,make an acute angle with the axis of the passage for the thread.

Brie) description of the drawings FIG. 1 is an axial section through aknown type of blowing device, which in accordance with the invention isprovided with a needle for pushing a weft into a passage through whichair is drawn by the blowing device.

FIG. 2 is an axial section through a blowing device provided with ashaft for sucking up a loop in a measured length of a thread andprovided with a needle for pushing into a passage in the blowing devicea part of the thread which remains within the shaft.

FIGS. 3-7 are diagrammatic representations in plan view of the blowingdevice according to FIG. 2 in which the successive steps for presentinga weft are indicated.

FIG. 8 is a perspective view of a loom embodying a weft-inserting deviceaccording to the invention.

FIG. 9 is a front elevation of the needle and its mounting shown in FIG.1.

FIG. 10 is a fragmentary plan view of the device shown in FIG. 2, withthe needle in the position shown in FIG. 5.

Description of the preferred embodiments The invention will be describedfirst with reference to FIG. 1, which is a simplified illustration ofthe device shown in FIG. 2, and in which some parts have been omittedand others have been rearranged to facilitate an understanding of theoperation of the parts shown in FIG. 1.

In a loom embodying a weft-inserting device according to the inventionuse can be made of device of the type described in application Ser. No.506,047, filed Nov. 2, 1965, which device includes a line 1 for airunder pressure, which line comes from a control valve and debouches intoa chamber 2 of an annular aperture 3 of a jet nozzle. The aperture 3surrounds the wall which encloses the passage 4. When air under pressurestreams out of the jet nozzle secondary air will be sucked through thepassage 4. A thread which is presented at the rear side 5 of the passage4 as hereinafter described will be drawn through the passage 4 as aresult of the stream of secondary suction air and further the stream ofsecondary air will carry the thread into the primary air, which streamsout of the jet nozzle, whereafter the thread is conveyed into the shedby the primary air. The insertion of the thread as well as its conveyingthrough the passage 4 can be accelerated by means of a needle 6. At itspoint the needle 6 is provided with a notch 7 so that a thread 8 whichruns in front of the needle 6 and behind the passage 4 will be engagedby the notch in the point of the needle.

By means of a screw 9 the needle is adjustably mounted to a slide 10,which fits in a guide 12 by means of a slide block 11. 13 is a part of adriving mechanism for the slide block, e.g. an eccentric driven rodwhich moves the slide block 11 and needle in synchronism with theoperation of the loom as hereinafter described. The driving of the slideblock 11 and the control of the valve in the line 1 are synchronized.

During the moment, in which the valve in the line 1 is opened or shortlbefore this moment the needle moves into ti e passage 4. During thismovement a thread which comes from a thread package 25 is inserted inthe shape of a loop into the passage by means of the notch 7 at thepoint of the needle. The needle 6 has sufficient clearance within thepassage 4 that the remaining ends of the thread 8 can extend along theneedle 6 Whereas there is still sufficient clearance for the secondaryair.

The insertion of the thread by means of the needle is also possible whenthe weft inserting device is provided with a shaft for temporarilystoring a measured length of a thread, which shaft can be considered asthe presenting device for the thread behind the blowing device.

Such a weft inserting device is shown in FIG. 2 and the line 14debouches into a chamber 2a, which chamber merges into an annular jetnozzle 3a. A mixing tube 14 is mounted at the down stream side of thejet nozzle 3a in which mixing tube primary air, which streams out of thejet nozzle, is mixed with secondary air which is supplied from the shaft15 through the passage 4a. The shaft 15 is provided with a suctionopening 17 which can be closed by a valve 16 as described in saidapplication Ser. No. 506,047 and in US. Patent No. 3,024,814. When thevalve 16 is opened a measured length of the thread is sucked into theinterior 18 of the shaft. When the valve 16 is closed air under pressurestreams out of the jet nozzle 3a and secondary air is sucked into theinterior 18 of the shaft through the opening 19 of which the valve 20meanwhile is opened. The passage 4a is connected to the front end 21 ofthe shaft. The shaft is provided with an entrance opening 22 for aflexible needle 6a near the front end of the shaft. The needle 6a ismounted in a slide 110, which runs in a guide 12a mounted on the shaft15. The interior of the shaft has a cleftlike cross section. Theentrance opening 22 for the needle 6:: is positioned in the plane ofsymmetry between the small sides of the cleft shaped interior of theshaft. The needle 6a makes an acute angle with the axis of the passage4a which is situated between the front end 21 of the shaft and the jetnozzle 3a. The passage 4a possesses a cross section which decreases fromthe front end 21 of the shaft in the direction of the jet nozzle 3a.

A thread 23 is drawn from a thread package 25 by means of continuouslydriven rollers 24 (FIG. 8). An auxiliary shaft 26 is positionedlaterally of the shaft 15. This auxiliary shaft has the function oftemporarily sucking up a loop in the thread 23 when the length of theloop in the thread within the shaft 15 has obtained its predeterminedsize and a thread clamp 27 has been closed by mechanism which operatesthe clamp 27 in synchronism with the operation of the loom as describedin US. Patent No. 3,024,814. The closed position of this thread clamp 27is indicated in FIGS. 6 and 7.

The thread, which has been inserted in front of the shaft by the pushingmember 30 as hereinafter described,

runs into the interior of the shaft 15 over a guide roller 28. Thethread clamp 27 and the valve 16 of the suction opening 17 are openedand the valve 20 to the air entrance opening 19 is closed in FIGS. 3, 4and 5. In these figures a loop in the thread 23 is sucked into the shaft15 whereas that moment is indicated in FIG. 5 in which the loop hasobtained its maximal length.

In FIGS. 3, 4 and 5 the leading end of the thread is clamped by acutting and holding device 29 as described in application Ser. No.506,047. The needle 6a is diagrammatically indicated. In FIG. 4 theneedle 6a brings the notch 7 at its point into the path of the thread,which runs before the front end 21 of the shaft 15. When the needle 6amoves further in the direction towards the jet nozzle 3a a loop isformed in this part of the thread, as indicated in FIG. 5. The loop inthe thread at the point of the needle is entirely formed when the needle6a takes its position as indicated in FIG. 6 and the cutting and holdingdevice 29 is opened, resulting in a releasing of the free end of thethread. At this moment the needle is already in the passage 4a. At thesame moment the valve 16 of the suction opening 17 is closed and thevalve 20 of the air entrance opening 19 is opened. Now the needle 6a isto be retracted, while the loop of the thread at its leadin end remainsin the passage 4a. The jet nozzle 3a becomes operative at the samemoment. This last situation is indicated in FIG. 7. When the jet nozzle3a becomes operative the thread is drawn entirely out of the shaft 15and is blown into the shed and thereby tensioned. When the reed hasperformed its beating action the thread runs thus through the mixingtube 14 and the passage 4a to the roller 28. When a new loop is to besucked into the shaft 15 a pushing member 30 becomes operative and movesto engage the thread 23 and to push a loop of the thread into the spacebetween the shaft 15 and the passage 4a, as described in application506,047, in order to insert the tensioned part of the thread in front ofthe mouth of the shaft, upon which the thread clamp 27 is released and anew loop can be sucked into the shaft 15. At this stage, after a newloop has been sucked into the shaft 15, the position of the thread is asshown in FIG. 5 except that the free end of the thread does not run tothe cutting and holding device 29 but instead runs through the mixingtube 14 into the fabric as hereinbefore described. At this stage the newloop of thread is cut off from the thread supply at a point between theroller 28 and the shaft 15, in the conventional manner as described inapplication Ser. No. 506,047 and in Patent No. 3,137,322, with theresult that the free end of the thread supply remains clamped in thecutting and holding device 29, and the cut-off end of the thread fallsin front of the inlet end of the passage 4a. In this way the new loop ofthread in the shaft 15 is severed from the thread supply in theconventional manner. The new loop which is stored in the shaft 15 atthis stage is the second part of an individual weft thread, and thefirst part of this individual weft thread is the part which has beenwoven into the fabric as hereinbefore described.

In FIGS. 3-4 only the first part of an individual weft thread is shown.Each individual weft thread, consisting of two parts or legs is to bewoven into the fabric in a hairpin like manner as known per se. After anext thread has been inserted into the shed from the opposite side, thesecond part of the individual weft thread is to be blown into the shedin order to leave the individual weft thread in the fabric in a hairpinlike formation. The insertion of the second part of the individual weftthread does not require any action of the part of the needle 6a, andtherefore forms no part of the present invention and is not shown inFIGS. 35. After the new loop of thread in the shaft 15, which forms thesecond part of the individual weft thread, has been blown into the shedthe shaft 15 and passage 4:: are empty. Then the pushing iember 30 isagain advanced as hereinbefore described,

to engage the thread which extends between the roller 28 and the cuttingand holding device 29, and to push a loop of the thread in front of theshaft 15, after which a new operation begins as illustrated in FIG. 3.

I claim:

1. A device for introducing a weft thread into a shed, comprising anozzle for blowing a stream of air, a

. passage having an outlet end adjacent the stream of air issuing fromthe nozzle and having an inlet end into which secondary air is drawn bythe jet action of the stream of air issuing from the nozzle in order toentrain an end of the weft thread presented at the inlet end of thepassage, and to carry such end of the thread through the passage to apoint at which such end of the thread is entrained by the stream of airissuing from the nozzle to cause a length of the weft thread to be drawnthrough the passage and blown into the shed, wherein the improvementcomprises a needle having a notch in its point, and mechanism forguiding the needle for axial movement from one extreme position in whichthe needle is retracted out of the path of the weft thread entering thepassage, through an intermediate position in which the notch in thepoint of the needle engages a weft thread at the inlet end of thepassage, to another extreme position in which the needle extends intothe passage and presents the weft thread inside of the passage.

2. A device according to claim 1 comprising a shaft extending from apoint adjacent the inlet end of the passage, which is adapted to take upby suction a measured length of the weft thread in the form of a loop,and which has an opening that receives the needle and extends in such adirection as to guide the point of the needle toward the inlet end ofthe passage and into engagement with an end of a loop of weft threadwhich has been taken into the shaft.

3. A device according to claim 2 wherein the passage decreases in crosssection from its inlet end toward its outlet end.

4. A device according to claim 2 wherein the shaft has a cleft-likeinterior, and the opening that receives the needle is so directed as toguide the point of the needle into the plane of symmetry between thesmall sides of the cleft-like interior of the shaft.

5. A device according to claim 4 wherein the opening that receives theneedle is so directed as to maintain the needle at an acute angle withthe axis of the passage.

6. A device according to claim 2 wherein the needle is driven by areciprocating slide block mounted on the shaft.

No references cited.

HENRY S. JAUDON, Primary Examiner.

